Photographic camera with a rear wall locking assembly



6 G. BEUTNAGEL ETAL 3,370,876

PHOTOGRAPHIC CAMERA WITH A REAR WALL LOCKING ASSEMBLY Filed Aug. 20,1965 F/G. E

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United States Patent 3,370,876 PHOTOGRAPHIC CAMERA WITH A REAR WALLLOCKING ASSEMBLY Gerhard Beutnagel, Wendhausen, and Herbert Weidner,Voikmarode, Germany, assignors to Voigtlander A.G. Filed Aug. 20, 1965,Ser. No. 481,160

Claims priority, application Germany, Sept. 12, 1964,

V 26,768 5 Claims. (Cl. 292-67) ABSTRACT OF THE DISCLOSURE A device,such as a photographic device, which must be opened and closed from timeto time. The device includes a housing member and a door member whichhas a closed position engaging and closing the housing member to preventaccess to the interior thereof. This door member also has with respectto the housing member an open position where the door member is at leastpartly spaced from the housing member to give access to the interiorthereof. A stationary lock element is fixedly carried by one of thesemembers and a movable lock element is carried by the other of the abovemembers and has a locking position engaging the stationary lock elementso as to lock the door in its closed position. A spring engages themovable lock element to yieldably maintain the latter in its lockingposition engaging the stationary lock element so as to maintain the doormember closed. A guide means is carried by the member which carries themovable lock element to guide the latter for movement in opposition tothe spring away from the stationary element so as to release the doormember for movement to its open position, and this guide means compelsthe movable element to carry out, in sequence, two distinctly differentangular and linear movements placing the movable element in a positionspaced from the stationary element to release the door only when themovable element has almost reached the end of the second of the abovemovements. A pair of stops are provided with one of these stops engagingthe movable lock element when it is in its locking position, and when itcarried out the first of its different movements the movable lockelements is moved away from this latter stop toward the other stop. Thisother stop limits the movement of the movable lock element while itcarries out the first of the pair of ditferent movements, and while themovable lock element engages the other of the stops it is still in itslocking relationship with respect to the stationary lock element andmust be moved along the latter stop while carrying out the second of themovements to release the door.

This invention relates to devices, such as photographic devices, whichmust be opened and closed from time to time.

Such devices conventionally include a housing having a door, formed, forexample, by the rear wall of the housing, which engages the housing in aclosed position of the door to prevent access to the interior of thehousing and which is at least partly spaced from the housing in an openposition of the door so as to give access to the interior of thehousing. With devices of this type it is of course conventional toprovide a lock structure between the housing and the door for releasablymaintaining the door in this position closing the housing.

When the device is a photographic device such as a camera, it isimportant to prevent accidental opening of the door since suchaccidental opening may result in undesirable exposure of film.Therefore, it is known to situate the lock structure of such devices atrelatively inaccessible protected locations to which the operator icecannot have accidental access so that the lock structure cannot beaccidentally actuated. Also, it is known to provide devices which have apair of independently operable locks both of which must besimultaneously placed in release positions in opposition to springforces, for example, in order to open the door. Of course, these knownstructures are relatively complex and inconvenient both because of theinaccessibility thereof, purposely provided for safety reasons orbecause of the relatively large number of parts, also provided forsafety purposes.

It is accordingly a primary object of the present invention to providefor a device of the above type a lock structure which is far simplerthan conventional lock structure and which is not located at arelatively inaccessible area of the device, at the same time providing avery high degree of safety against unintentional unlocking of the door,such as by accidental engagement of the lock actuating element.

In particular it is an object of the invention to provide a lockstructure which compels the operator to displace a movable lock elementsequentially through at least two distinctly different movements beforethe lock structure releases a door for movement to its open position.

Also, it is an object of the invention to provide a lock structure whichis exceedingly compact so that it occupies only a relatively smallamount of space.

In addition, it is an object of the invention to provide a lockstructure which is very easy to manipulate in a manner which does notrequire the operator to memorize in advance a particular type ofoperation or series of operations which must be carried out in order forproper manipulation of the lock.

Primarily, with the structure of the invention the device, whichincludes a housing member and a door member movable between closed andopen positions relative to the housing member, has a stationary lockelement carried by one of these members and a movable lock elementcarried by the other of these members, and the movable lock elementengages the stationary lock element to retain the door member in itsclosed position, a spring means acting on the movable element toyieldably maintain the latter in its position holding the door member inits closed position. According to the invention a guide means guides themovable lock element for movement away from the stationary lock elementto release the door for movement to its open position, and this guidemeans of the invention compels the movable lock element to carry out insequence two distinctly different movements, with the guide meansplacing the movable lock element in its position releasing the door onlywhen the movable lock element has almost completed the second of the twomovements.

The invention is illustrated by way of example in the accompanyingdrawings which form part of the application and in which:

FIG. 1 is a partly broken away, partly sectional plan view showing thestructure of the invention as applied to a camera with the lockingstructure shown in FIG. 1 in its locking position;

FIG. 2 shows the structure of FIG. 1 in a different position which theparts take when a movable lock element has almost reached its releaseposition.

Referring to the drawings, there is illustrated therein a camera housing1 which is shown in the drawings as it appears when looking toward oneend of the camera housing. The front wall of the camera housing carriesan objective 2 which is fragmentarily illustrated and which forms nopart of the present invention. The housing 1 carries a door 3 movablebetween the closed position illustrated in the drawings and an openposition, this door 3 preventing access of the operator and light to theinterior of the housing when the door 3 is in its closed position whilegiving access to the interior of the housing when the door 3 isdisplaced away from the housing 1 to an open position. This door 3, atits end distant from that which is illustrated in FIGS. 1 and 2 may behingedly connected to the housing 1 so as to be turnable relativethereto between the illustrated closed position and an open position.

The lock means of the invention is carried in part by the door member 3and in part by the housing member 1 for releasably holding the doormember 3 in its closed position, and this lock structure is situated ina space which is defined between a part of the housing 1 and a wall 4which is fixed to the housing 1. Thus, the housing 1 is in part coveredby the wall 4 which extends beyond a shoulder 12 of the housing 1 so asto define with the latter a space in which the lock structure isaccommodated. The door 3 has at its end which is visible in the drawingan edge portion which projects into the space or gap between the housing1 and the wall 4 which is fixed thereto, and in the illustrated example,the door 3 carries a stationary lock element 5 in the form of a memberof suitably hook-shaped configuration. In the closed position of thedoor this stationary element 5 is engaged by a lever 6 of a movable lockelement 7 in the form of a suitable lever capable of being manipulatedby the operator in the manner described below. A guide means guides themovable lock element 7 for movement toward and away from its lockingposition engaging the stationary element 5, and in accordance with theinvention the guide means guides the element 7 so as to compel it tomove in sequence through two distinctly different movements before theelements can reach a position releasing the element 5 so as to releasethe door 3 for movement to its open position. This guide means includesa portion of the lever 7 which is formed with the elongated slot 8 and astationary pin 9 carried by the housing 1 and extending through the slot8 to form a pin-and-slot connection therewith. As a result of thisconstruction the lever 7 can turn as well as move linearly with respectto the pin 9. Thus, in the illustrated example angular and linearmovements are the two distinctly different movements which the guidemeans of the invention compels the movable element 7 to carry out. Aspring means 10 yieldably maintains the movable lock element 7 in itsposition engaging the stationary lock element 5 to maintain the door inits closed position, and in the illustrated example this spring means 10is in the form of a suitable wire spring coiled about a stationary pincarried by the housing 1 and having a free end engaging the lug 6 so asto urge the lever 7 on the one hand toward the left, as viewed in FIGS.1 and 2 and on the other hand in a clockwise direction about the pin 9,as viewed in FIGS. 1 and 2, Thus, the spring means 10 yieldably holdsthe movable lock element 7 in its position shown in FIG. 1 where thelever 7 engages the shoulder 12 which forms a stop limiting theclockwise turning of the lever 7 by the spring 10. The lever 7 has afree end 11 which is suitably knurled so that the operator can easilygrasp the end 11 of lever 7 for manipulating the latter.

When the parts are in the position shown in FIG. 1 a means of theinvention cooperates with the lever 7 to prevent linear movement thereofcompelling the operator to turn the lever 7 in the direction of thearrow 15 before it is possible to provide any linear movement of thelever 7. Thus, the left end of the slot 8 cannot be advanced toward thepin 9, which engages the right end of the slot 8, as viewed in thedrawings, until after the lever 7 hasbeen turned by the operator througha given angular distance from its position shown in FIG. 1. This meanswhich prevents linear movement of the lever 7 when it has the positionof FIG. 1 includes portions of the housing 1 and lever 7 one of which isformed with a cutout and the other of which projects into this cutout.In the illustrated example it is the lever 7 which is formed with thecutout 14 and it is the housing 1 which carries a projection 13projecting from its shoulder 12 into the cutout 14 so as to preventmovement of the lever 7 to the right, as viewed in FIG. 1.

Therefore, when the operator engages the end 11 of the lever 7 to unlockthe door 3, the operator must move the end 11 in the direction of thearrow 15, since no other movement is possible. Moreover, this movementmust continue until the lever 7 at least approximately reaches theposition shown in FIG. 2 where the projecting portion 13 of the housing1 is situated beyond the cutout 14 of the lever 7, and at this time thelever 7 engages a stationary pin 16 carried by the housing 1 and forminga second stop limiting the movement of the lever 7 away from the firststop which is formed by the shoulder 12. At this time, as

shown in FIG. 2, the lug 6 still engages the stationary lock element 5',so that the door 3 is still maintained in its closed position. When theparts have reached the position shown in FIG. 2, it is essential for theoperator to advance the lever 7 in the direction of the arrow 17 showninFIG. 2, so as to displace the left end of the slot 8 toward the pin 9,before it is possible for the lug 6 to move away from the stationarylock element 5 for releasing the door 3. It is only just before the leftend of the slot 8 reaches the pin 9, in opposition to the spring 10,that the lugs 6 will have reached a position displaced from thestationary lock element 5 so as to release the door 3.

Of course, with the door 3 in its open position the operator willrelease the element 7 which will be returned by the spring 10 to theposition illustrated in FIG. 1. Then when the operator displaces thedoor 3 back to its closed position, the inclined edge 18 of thestationary lock element 5 will engage and ride along the left edge ofthe lug 6, as viewed in FIGS. 1 and 2, compelling the element 7 first toturn in the direction of the arrow 15 and then to be displaced in thedirection of the arrow 17 before the element 7 snaps at its lug 6 behindthe stationary lock element 5 whereupon the spring 10 will return thelever 7 to its position shown in FIG. 1.

It is therefore apparent that with the particular embodiment of theinvention shown in FIGS. 1 and 2 in order to unlock the door 3 theoperator must first turn the lever 7 and then displace it linearly, andthe guide means of the invention which compels the movable lock elementto carry out in sequence these two distinctly different movementsprovides a perfectly safe locking structure which will not release thedoor 3 even if it should happen that the end 11 of the member 7 isaccidentally engaged and moved. There is practically no chance that anyunintentional or accidental movement of the lever 7 will first turn itin the direction of the arrow 15 and then displace it linearly in thedirection of the arrow 17,'so that the locking structure of theinventionis highly reliable while at the same time being quite simple andcompact.

Of course, it is emphasized that the basic idea of compelling themovable lock element to carry out the two distinctly different movementsin sequence can be embodied in different structures. For example, .thelever 7 may be provided with a slot of angular configuration having apair of legs which extend in different directions compelling theoperator first to move one leg of the slot relative to the pin and thento move the other leg of the slot relative to the pin before the movablelock element reaches its release position, and in this way also it ispossible to provide two distinctly different movements which theoperator must carry out in sequence before the door will be released. Itis also possible to provide a structure where the pin of thepin-and-slot connection is flattened at one side while the slot is ofcircular configuration at one end and has projecting from this endofcircular configuration an elongated narrow portion which must have apredetermined angular position relative to the pin where the flattenedside thereof will slide along one edge of the slot before the lever canbe linearly moved relative to the pin, so that with such a constructionalso the lever must be turned from one end position relative to the pinthrough a given angle before the slot has reached the required angularposition which will permit linear movement of the lever relative to thepin.

While variations of this general type are indeed possible in carryingout the invention, the particular structure shown in the drawings anddescribed above is preferred because it is quite simple and inexpensivewhile at the same time being highly compact and very reliable anoperation.

What is claimed is:

1. In a device, such as a photographic device, which must be opened andclosed from time to time, a housing member, a door member having aclosed position engaging and closing said housing member to preventaccess to the interior thereof, said door member also having withrespect to said housing member an open position where said door memberis at least partly spaced from said housing member to give access to theinterior thereof, a stationary lock element fixedly carried by one ofsaid members and a movable lock element carried by the other of saidmembers and having a locking position engaging said stationary lockelement for locking said door in the said closed position thereof,spring means engaging said movable lock element for yieldablymaintaining the latter in its locking position engaging said stationarylock element to maintain said door member in said closed positionthereof, guide means carried by said other member and guiding saidmovable lock element for movement in opposition to said spring meansaway from said stationary element to release said door member formovement to said open position thereof, said guide means compelling saidmovable element to carry out in sequence two distinctly differentangular and linear movements and placing said movable element in aposition spaced from said stationary element to release said door onlywhen said movable element has almost reached the end of the second ofsaid movements in opposition to said spring means and a pair of stopsone of which is on said housing member and engages said movable lockelement to determine its locking position and the other of which issituated in the path of movement of said movable lock element away fromsaid one stop while said movable lock element carries out the first ofsaid movements, said other stop determining the end of said firstmovement and said movable and stationary lock elements still being inlocking relationship with respect to each other when said movable lockelement engages said other stop, and said movable lock element carryingout the second of said movements while engaging said other stop.

2. In a device as recited in claim 1, said movable lock element being inthe form of a lever and said guide means including a portion of saidlever formed with an elongated slot and said guide means including a pinfixed to said other member and extending into said slot for providingpin-and-slot guiding of said lever permitting both angular and linearmovements thereof, said spring means maintaining said lever in saidlocking position engaging said one member with one end of said slotengaging said pin, and one of said members carrying said one of saidstop which engages said lever to determine an angular end positionthereof when said one end of said slot engages said pin and said leveris in its locking position, said lever and one of said membersrespectively having a pair of portions one of which is formed with acutout and the other of which projects into said cutout for preventinglinear movement of said lever in a direction displacing the other end ofsaid slot toward said pin as long as said lever engages said one stop,said lever when turned in opposition to said spring means displacingsaid lever away from said one stop displacing said portions away fromeach other to a position where they no longer prevent the linearmovement of said lever displacing said other end of said slot towardssaid pin when said lever has been turned in opposition to said springmeans through a given angle into engagement with said other stop, thesecond of said movements being linear movement of said lever displacingthe other end of said slot towards said pm.

3. In a device, such as a photographic device, which must be opened andclosed from time to time, a housing member and a door member having aclosed position engaging and closing said housing member to preventaccess to the interior thereof, said door member having an open positionat least partly spaced from said housing member to give access to theinterior thereof, an elongated locking lever, pin-and-slot meansconnecting said lever to one of said members for linear and angularmovement relative thereto, a stationary lock member carried by the otherof said members and engaged by said lock lever when said door member isin said closed position thereof for maintaining said door member in saidclosed position, spring means acting on said lever for yieldablymaintaining the latter in said position engaging said stationary lockmember to maintain said door member inrsaid closed position thereof, afirst stop carried by one of said members and engaged by said lever whenthe latter is maintained by said spring means in said position holdingsaid door member in said closed position, means engaging said lever tocompel the latter to turn away from said stop in opposition to saidspring means before said lever can be linearly displaced to a positionreleasing the said door member, and a second stop situated in the pathof movement of said lever away from said first stop to determine the endof the angular movement of said lever, said lever being linearlydisplaced after it engages said second stop and still having its lockingrelationship with respect to said stationary lock member at the end ofsaid angular movement when said lever initially engages said secondstop.

4. In a camera, a camera housing, a door having a closed positionengaging said housing for closing the latter and preventing access tothe interior thereof, said door having an open position at least partlyspaced from said housing to give access to the interior thereof, astationary lock member carriedby said door, a movable lock lever carriedby said housing, pin-and-slot means carried by said housing and guidingsaid lever for linear and angular movement relative to said housing,said lever cooperating with said stationary lock member for maintainingsaid door in said closed position, spring means carried by said housingand engaging said lever for maintaining the latter in engagement withsaid stationary lock member for yieldably retaining said door in saidclosed position, a first stop carried by said housing and engaged bysaid lever when the latter is maintained by said spring means in saidposition holding said door in said closed position thereof, and saidlever and housing respectively having portions one of which is formedwith a cutout and the other of which projects into said cutout forpreventing linear movement of said lever until after the latter has beenturned away from said stop through a given angular distance inopposition to said spring means, and a second stop situated in the pathof movement of said lever away from said first stop and engaged by saidlever after it turns through said given angular distance, whereupon saidlever may then be moved linearly in opposition to said spring means to aposition releasing said door for movement to its open position.

5. In a device, such as a photographic device, which must be opened andclosed from time to time, a housing and a door operatively connectedthereto for movement between a closed position closing the housing andan open position opening the housing, a stationary lock element carriedby said door, and a movable lock element carried by said housing andengaging said stationary lock element for maintaining said door in saidclosed position thereof, spring means engaging said movable lock elementmaintaining the latter in its position engaging said stationary lockelement to maintain said door in said closed position, said movable lockelement being in the form of a lever formed with an elongated slot andhaving a pair of opposed side edges one of which is formed with acutout, said housing carrying a pin and having a projection situated insaid cutout to prevent linear movement of said lever, so that saidlever' must first be turned to displace said cutout beyond saidprojection before said lever can be linearly displaced. to be placed ina position releasing said door, and said housing carrying a pin engagingthe side edge of said lever opposed to that which is formed with saidcutout for guiding said lever for movement after said lever has beenturned through an angle sufiicient to displace said cutout beyond saidprojection, and said housing having a shoulder which eninto engagementwith the latter pin, whereby said shoulder determines the initialposition of said lever.

References Cited UNITED STATES PATENTS Kanaly 2921 14 Weel 292-67 Egbert292145 Underwood. Moseley 292114 Anderson 29267 X Duttine 70-70 XSwanson 70-70 MARVIN A. CHAMPION, Primary Examiner.

EDWARD C. ALLEN, Examiner. gages said lever before it 1s moved throughsaid angle 15 I R. MOSES Assistant Examiner-

